Motor controller



May 13 1924, 1,494,230

H. N. FOCHS MOTOR CONTROLLER 32 NWW Wl TNESSES lNVE/VTUH HERBERT /V.Foc/i6 TTHNEYS Plasma my i3, i924.

UNITED STATES PATENT OFFCE.

HERBERT E m8, 0l' NEW You, I. Y.

KOTOR OUITBOLLEB.

To all whom it may concern.'

Be it known that I, Hnnnnn'r N. Foons, a citizen of the United States,and a resi dent of the city of New York, borough of Manhattan in thecounty of Manhattan and State of ew York, haveinvented a new and Imroved Motor Controller, of which the fol owing is a full, clear, andexact description.

This invention relates to a motor controller and has for an object aprovision of a circuit and apparatus whereby the direction of motion ofa motor may be simly and easily reversed by means of a contro er inwhich only two wires are required to ex tend between the source of powerand the controller and the motor.

A further object resides in the provision of means whereby themanipulations required to operate the device is reduced to a minimum andwhereby the current consumption entailed by the operation of this deviceis only very slightly above the normal operatinghcurrent for the motorwhen running in eit er direction.

A still further object resides in the particular construction and arranent of parts hereinafter described and c aimed and shown in the'accompanying drawing.

In neral the invention com rises a combination of a motor with its eldwinding and reversin switch, a magnet for operat in the switc aresistance rheostat and circuit connections between these variousdevices whereby the simple manipulation of the controller handle in onedirection or another will result in the closing of the circuit and theoperation of the motor into the desired direction.

The invention is illustrated in the drawin? of whiche igure 1 is a planview of the operating ma et and reversing switch.

igure 2 is a side elevation of the same.

Fi re 3 is a detailed illustration of one position of the switchcontact, preferably the normal position.

Figure 4 is an illustration of the position of the switch` contacts whenthe switch is midway in its movement from one position to another.

Figure 5 is an illustration of the position of the switch contacts whenthe switch isn an abnormal position.

Figure 6 is a di representation of the circuit a involved in the use ofthis system.

Figure 7 is a detailed view of a modified circuit. j

As shown in the drawings, the referred foi-m of my invention comprises te use of an electromagnet 1, reversing switch 2, a motor 3, having afield winding 4 and a suitable rheostat resistance 5, with an o eratingarm 6, capable of being moved in either direction.

As shown in Figures 1 and 2 the apparatus including the operating magnetand reversiii switch, comprises a suitable base 7, pre erably the insulamaterial. On this base is fastened a suitable bracket 8 to which a pairof magnet coils 9 and 10 are connected. Adjacent the poles 11 and 12 ofthese coils an amature plate 13 is suitably pivoted to the base portion7. On its rear up er face 'this armature carries an insulating r 14,from the ends of which project contacting studs such as 15. Each ofthese studs are adapted in accordance with the movement of the amatureto move back and forth between two ring contact blades, such as 16 and17. ese blades are suitably connected to the base 7 and are spacedtherefrom electrically by means of insulating plate 18.

The normal retracted position of the armature as shown in Figures 1 and2 is such that the studs 15 bear their back contacts as shown parti lyin Figure 3. This retracted position is maintained by reason of aconnection with the rear of the armature of spring 19 connected to anad- 'ustable shaft 20 threaded in a suitable earing 21 on a pedestal 22mounted on the base 7. This. shaft can be manipulated by means of thumbnut 23.

The spring blades 16 and 17 are so ositioned and adjusted that as thestu s 15 vmove tothe left, contact is made by the studs witbthe blade17, before the contact Vwith the blades 16 have been broken. As

will be readily seen hereinafnthis short circuits the motor temporarilyto prevent undue sparking and conductive discharges.

Referring' to Fi re 6, which represents the circuit involve in thissystem;I a wire 24 leads from the plus side of the source of power tothe coil 10 and thence to the coil 9.

A wire 26 extends from the coil 9 to one end of the field winding 4.'From there a wire 27 extends to a contact 28 of the reversing switch.This contact is connected by a wire 29 to a front contact 80. The minusside of the source of power is connected by a wire 31 to a controllerarm '6. This arm is adapted to be moved in either direction. If moved incounter-clockwise direction from the full line position shown in Fi re6, this arm is adapted to contact with e right hand end of resistance 5.If it swings in a clockwise direction from the full line osition the arm6 closes the circuit 1 at t e left hand end of the resistance 5. In thissecond movement, therefore, the circuit is closed with the resistanceout of circuit, whereas in the other direction of movement the circuitis first closed with all the resistance 5 in circuit 3. A wire 32extends rom the left hand of resistance 5 to a rear contact 33 on thereversin switch. A wire 34 connects this contact wi a front contact 35.The upper brush 36 of the motor 3, as viewed in F1 re 6, is connected bya wire 37 to one of t e studs 15, whereas the other brush 38 of themotor 3 is connected by a wire 39 to the other contact stud 15.

In Figure 7 the wires 32 and 81, leading to the resistance controllerare shown together with the arm 6. In this modication, however, tworesistances areused, one resistance 40 and the other 41, each having adiferent predetermined view. The normal position of the switch arm ,isintermediate these resistances. The right hand end of the resistance 41is connected to the left hand end of resistance 40 by means of a wire42.

In the operation of the device we will first assume that the controller6 is in the position shown in full lines in Figure 6. Assuming that itis moved then in a counter-clockwise direction, it first contacts andmakes a circuit with the entire resistance in the circuit. This causesthe current to iow through the ma net, the reversing switch and themotor wit its winding, with the switch in its retracted osition. Theview of the resistance 5 figure with respect to the other resistance inthe circuit is such that the currentthus produced is nsuicient toenergize the magnet strongly enough to throw t e switch and therefore te armature remains on the back 'contacts and the motor, for example,will incasso cluded in thecircuit are such that this starting current issuiicient to energize the magnet strongly enough to pull over thearmature and cause the studs 15 to contact with their front contacts 35and 30. A consideration of Figure 6 will disclose that this movement ofthe armature reverses the direction of iiow of the current through thearmature of the motor, whereby the motor will then move in the op ositedirection. After the motor is started t e rheostat arm 6 can be moved tothe right hand end of the' resistance 5 since after the armature 13 ismoved over adjacent the poles 11 and 12 of the magnet it requires verylittle current to keep it over in this position.

The value of the resistance 5 and the sen sitiveness of the adjustmentof the spring 19 can be so predetermined that it4 requires only a verysmall Aamount of current above normal to flow through the magnet andcause the operation of the switch. It will be observed that from themagnet and the rheostat on] two wires extend to the motor. It will alsoobserved that from the rheostat and the source of power only two wiresextend to the magnet and the switch so that the rheostat may be locatedat any distance from the motor and requires only the use of a minimumamount of wire to lead therebetween. It will also be perceived that thema net, the field winding, motor armature an the rh` stat are all 1nseries through the reversin switch, an arrangement which requires aminimum amount of conductor wire.

What I claim is 1. A motor controlling system which comprises a motorand reversin switch, a magnet for operatin said switch, a rheostat andconnections t erebetween, said rheostat and s aid connections beingadapted to operate the switch and connect the motor for olperation inone direction or another upon t e movement of the rheostat arm in onedirection or another to close the circuit at either end of the rheostatresistance.

2. A motor controlling circuit and apparatus, which comprises a.reve-rein -switchoperating magnet, motor field winxngs and a reversingswitch, a motor armature, a rheostat resistance, and a rheostat arm, alldisposed in series.

3. A motor controlling circuit and a paratus which comprises a reversinswitc a ma net for operating said switc a motor fiel winding and motorarmature, a rheostat resistance, a rheostat arm, all disposed in series,and -a source of power, connections from the source of power tosaid aparatus, the said rheostat resistance bein o such value that when therheostat arm c oses the circuit at one end of the resistance the currentliowing in the circuit will be insufficient to operate the l reversingswitch whereas when the rheostat arm closes the circuit at the other endof the resistance, starting current is Sullicient. to energize themagnet strongly enough to throw the reversing switch.

4. A motor controlling apparatus and circuit which comprises arevcrsmg-switch-o meting magnet, a motor n id n iield win ing andreversing switch and I rheostct, all connected in series, s, source ofpower lo a single wire leadin from the source o power to one side of temagnet and a single wire leading'from the source` of power to the arm ofthe rheostat.

HERBERT N. FOCHS.

